
In this series of Blogs we look to breakdown some of the jargon used in biodiversity, sustainability and conservation. In the first of such blogs we look at blue carbon.
What is it?
Blue carbon is the carbon captured and stored in coastal and marine ecosystems though you may hear the term ‘sequestered’ being used for this. The species and ecosystems that capture and store the most carbon are:
- Mangroves
- Salt marsh
- Seagrass
- Algae
Figures suggest that up to ten times more carbon is captured and stored by these ecosystems than a rainforest per unit area. However we are now realising that there are many more habitat types within the ocean environment that are important for carbon storage and these include thick muds, maerl reefs and many more. Acting as net carbon ‘sinks’ these ecosystems have a role to play in the mitigation of climate change. These ecosystems also provide essential services including coastal protection, food production and sustainable livelihoods and providing important habitats for marine life.
There IUCN estimate that 83% of global carbon is circulated through the oceans, with coastal habitats only covering 2% of the total ocean area but storing 50% of the total carbon sequestered in ocean sediments (source: IUCN).
What is the issue?
Human activities such as commercial fishing / direction exploitation of organisms, land use change / degradation, pollution, invasive species can damage these areas leading to the release of carbon dioxide into the atmosphere which contribute to climate change. These activities also lead to a loss of biodivesity and ecosystem service provision.
It is estimated that Mangroves are being lost at a rate of 2% per year, tidal marshes at 1-2% per year and sea grass beds are diminishing by 1.5% per year despite active planting programmes.

What can be done?
Dedicated conservation programmes can be established to halt the decline in coastal habitats. These can include creating marine protected areas (MPAs), however the pressing issue is to halt the destruction of these ecosystems through education, delivering sustainable livelihoods, engaging with local communities and promoting the importance of these ecosystems. Relying solely on the creation of MPAs is not enough and we need to manage human behaviour and their activities that disrupt and damage these fragile ecosystems before it becomes too late to halt the loss and destruction.
